1. Field of the Invention
The invention relates to a shift gearbox having two gears. An input shaft of the gearbox can be driven by an electric machine, and the input shaft is connected via at least one single-direction clutch to an output shaft of the gearbox.
2. Description of the Related Art
A known shift gearbox is used in conjunction with an electric machine with a rotor shaft that holds first and second spur gears. The first spur gear is connected fixedly to the rotor shaft and the second spur gear can be connected rotationally conjointly to the rotor shaft when a clutch is closed. The first spur gear meshes with a third spur gear that is mounted, via a freewheel, on a second shaft. The second shaft rotationally conjointly holds a fourth spur gear that engages with the second spur gear of the rotor shaft that can only be activated by the clutch. The shaft to which the freewheel of the gearbox is assigned rotationally conjointly holds a fifth spur gear that interacts with a gearwheel of a differential. Two wheels at the sides of a motor vehicle are assigned to two axle sections of an axle of the motor vehicle and can be driven via the differential.
A disadvantage of the configuration of this known shift gearbox is that the spur gears mounted on the rotor shaft are engaged permanently with the spur gears of the shaft arranged parallel to the rotor shaft.
The freewheel used in the gearbox is a single-direction clutch. If the other clutch is closed, the spur gear assigned to the clutch is connected rotationally conjointly to the rotor shaft, and the shaft arranged parallel to the rotor shaft is driven at such an angular velocity that the freewheel is overtaken. Accordingly the torque is transmitted with the freewheel being bypassed.
It is an object of the invention to develop a shift gearbox so that simple shifting of the gears of the gearbox is possible with a simple design.